Regenerative coke furnace and method of heating it

ABSTRACT

A REGENERATIVE COKE FURNACE WITH RESPECTIVELY VARYING UPPER AND LOWER LOCATED BURING POINTS WITH HEATING FLUES COMBINED IN GROUPS OF TWO OR FOUR. REGENERATOR COMPARTMENTS CORRESPONDING TO THE NUMBER OF GROUPS OF HEATING FLUES ARE CONNECTED VIA SOLE FLUE COMPARTMENTS WITH REGULATING DEVICES ARRANGED AT THE EXTERIOR SIDE OF THE FURNACE FOR CONTROLLING THE FLOWING MEDIA SUCH AS AIR, POOR OR LEAN GAS AND WASTE GAS. THE REGENERATING COMPARTMENTS ARE LONGITUDINALLY SEPARATED INTO LONGITUDINAL REGENERATOR SPACES OR PARTS BY A WALL AND THE CONNECTING FLUES FOR THE LOWER LOCATED BURNING POINTS ARE CONNECTED TO ONE LONGITUDINAL PART AND THE CONNECTING FLUES FOR THE UPPER LOCATED BURNING POINTS TO THE OTHER LONGITUDINAL PART. EACH REGENERATOR SPACE OBTAINED BY THE LONGITUDINAL DIVISION WITHIN THE REGENERATOR COMPARTMENT BY THE LONGITUDINAL DIVISION OF THE SOLE FLUE COMPARTMENTS HAS AN INDEPENDENTLY DOSABLE OR CONTROLLABLE FLUE. ADJACENT HEATING FLUES HAVE DIFFERENT LEVELS FOR THEIR RESPECTIVE UPPER BURNING POINT OPENINGS, AND FOR THEIR RESPECTIVE MIDDLE, BURINING POINT OPENINGS, WHICH EACH HAS TWO BOTTOM OR LOWER GENERALLY COPLANAR BURNING POINT OPENINGS. EACH FLUE IS ALSO PROVIDED WITH A CENTRAL RICH GAS INLET AT A LEVEL SUBSTANTIALLY BELOW THE MIDDLE AND UPPER BURNING POINTS AND GENERALLY COPLANAR WITH OR SLIGHTLY ABOVE SAID TWO LOWER BURNING POINTS. OWING TO THE SELECTION OF DIFFERENT LEVELS FOR THE UPPER AND MIDDLE BURNING POINT OPENINGS FOR ADJACENT PAIRS OF FLUES, A TOTAL OF FIVE DIFFERENT COMBUSTION LEVELS IS PROVIDED FOR ANY TWO CONSECUTIVE OR ADJACENT PAIRS OF HEATING FLUES WHICH PROVIDES A PARTICULARLY ADVANTAGEOUS DISTRIBUTION OF HEAT IN THE VERTICAL DIRECTION OF THE HEATING WALLS IN PARTICULARLY HIGH FURNACES. THE FLUES HAVE DOSING OPENINGS HAVING REGULATING INSTALLATIONS LOCATED ON THE OUTSIDE OF THE FURNACE WHICH WHEN HEATING WITH POOR OR LEAN GASES ARE PROVIDED WITH DIFFERENT CROSS-SECTIONAL AREAS OF PASSAGE. AN IMPROVED PROCESS IS ALSO DISCLOSED WHEN HEATING WITH LEAN GAS, WHICH SETS FORTH QUANTIATIVE RATIOS OF THE LEAN GAS AND COMBUSTION AIR AT THREE VARIOUS LEVELS OF COMBUSTION.

Sept. 5, 1972 s E l ETAL REGENERATIVE COKE FURNACE AND METHOD OF HEATING IT Filed March 10, 1970 4 Sheets-Sheet 1 w T. fi

H QC A. STEDING ET AL Sept. 5, 1972 REGENERATIVE COKE FURNACE AND METHOD OF HEATING IT Filed March 10, 1970 4 Sheets-Sheet 2 Sept. 5, 1972 A. STEDING ETAL REGENERATIVE COKE FURNACE AND METHOD OF HEATING IT Filed March 10, 1970 4 Sheets-Sheet 5 fi/w/ HIV M United States Patent REGENERATIVE COKE FURNACE AND METHOD OF HEATING IT Artur Steding, Drusenbergstr. 6, Bochum, Germany, and

Manfred Blase, Hufelandstr. 60, Essen, Germany Filed Mar. 10, 1970, Ser. No. 18,064 Claims priority, application Germany, Mar. 12, 1969, P 19 12 390.1

Int. Cl. Cb 21/22 US. Cl. 201-41 3 Claims ABSTRACT OF THE DISCLOSURE A regenerative coke furnace with respectively varying upper and lower located burning points with heating flues combined in groups of two or four. Regenerator compartments corresponding to the number of groups of heatmg fines are connected via sole flue compartments with regulating devices arranged at the exterior side of the furnace for controlling the flowing media such as air, poor or lean gas and waste gas. The regenerating compartments are longitudinally separated into longitudinal regenerator spaces or parts by a wall and the connecting flues for the lower located burning points are connected to one longitudinal part and the connecting lines for the upper located burning points to the other longitudinal part. Each regenerator space obtained by the longitudinal division within the regenerator compartment by the longitudinal division of the sole flue compartments has an independently dosable or controllable flue. Adjacent heating flues have different levels for their respective upper burning point openings, and for their respective middle burning point openings, which each has two bottom or lower generally coplanar burning point openings. Each flue is also provided with a central rich gas inlet at a level substantially below the middle and upper burning points and generally coplanar with or slightly above said two lower burning points. Owing to the selection of different levels for the upper and middle burning point openings for adjacent pairs of lines, a total of ,five different combustion levels is provided for any two consecutive or adjacent pairs of heating flues which provides a particularly advantageous distribution of heat in the vertical direction of the heating walls in particularly high furnaces. The flues have dosing openings having regulating installations located on the outside of the furnace which when heating with poor or lean gases are provided with different cross-sectional areas of passage. An improved process is also disclosed when heating with lean gas, which sets forth quantitative ratios of the lean gas and combustion air at three various levels of combustion.

The invention relates to a regenerative coke furnace having upper, middle and lower located burning points.

The present invention is an improvement of the invention described in US. application Ser. No. 762,681 filed Sept. 26, 1968, now issued US. Patent No. 3,567,588, entitled Regenerative Coke Furnace With Upper and Lower Located Burning Points having heating flues combined in groups and regenerator compartments corresponding to the number of groups of heating flues, which are in connection -via sole flue compartments with regulating devices arranged at the exterior side of the furnace for dosing or controlling the flowing media (air, poor gas and waste gas).

In order to improve the heating of said furnaces it has been proposed essentially that the regenerator compartments be longitudinally separated by a wall and the connecting flues for the upper located burning points be connected to the one and the connecting flues for the lower Patented Sept. 5, 1972 located burning points to the other longitudinal part. Furthermore, to each regenerator space obtained by the longitudinal division within the regenerator compartment by the longitudinal division of the sole flue compartments an independently dosable flue is correlated which is regulated by means of the regulating device. In this way the flowing media can be adjusted at the burning points of the heating walls so that also in extremely high furnaces a distribution of the temperature is obtained adapted to the actual heat requirement of the furnace chambers not only as heretofore in a horizontal, but also in a vertical furnace direction, since when the requirement arises it is not only possible to adjust within a group of heating flues the consumption of combustion media for the upper and lower burning points independently from each other, but also the' consumption of media of the upper or lower burning points of groups of heating fiues towards groups of heating flues. Thereby it is simplified for the operator after the furnace has been started to remove or compensate local overheatings or heat shadows occurring on the heating walls by a corresponding change of the dosage on the regulating devices.

An object of the present invention is, particularly in the case of heating with poor or lean gases, to further improve by simple means through additional regulating devices the adjusting of the heat input in each area of the heating walls, in accordance with the heat requirement which exists there.

It is known particularly in the case of coke furnaces which are heated with rich gases, that burning points at different heights of the heating flues are provided or that rich gas is introduced through a single nozzle on the bottom of each heating flue and that at different heights of the heating fiues dosed air is added in order to obtain several burning points in a vertical direction.

It is also known that when heating with poor gases, it is necessary to provide in a heating flue two burning points located at different heights, which in each case are formed by an air flue and a gas flue ending on the same plane.

In a further construction of the furnace the present invention proposes, that the heating flues comprise burning point openings one upper, one middle and two on the floor surface, whereby their component parts of the regulating installations belonging to it and forming dosing openings are located on the outside of the furnace, when heating with poor gases they are provided with different cross-sectional areas of passage. This allows when using for instance an over-stoichiometrical, and under-stoichiometrical and a stoichiometrical or almost stoichiometrical combustion in the heating flues with the customary four burning point openings in the heating flues, the reaching of the three burning points located at different heights in a heating flue without an additional number of flues for conveying the media, which in turn constitutes a better adaptation of the heat supply of the heating flues to the heat requirement of the heating walls.

A further object is to provide an improved heat adaptation which becomes even more effective with respect to the whole coke furnace block, when the middle and the upper burning point openings of a heating flue show height differences as compared to the same or corresponding openings inside a heating wall as well as to those of neighboring heating flues in a longitudinal axis of a block. The procedure for operating such coke furnaces when heating with poor gas according to the invention, consists essentially in that through adequate setting of the dosing openings provided in the regulating device at the burning point openings of a heating flue a combustion with excess air takes place, whereas at the middle burning point opening the outflowing gas burns with an excess of gas and at the upper burning point opening the outflowing air causes the combustion of the remainder. In order to proceed effectively the dosing openings on the outer side are set in such a way, that the bottom burning points of the heating flues are fed with for instance around 40% of the total amount of poor gas and 60% of the total air amount, whereby the remaining 40% of the air amount flows out of the upper burning point opening and the remaining 60% of the gas amount flows out of the middle burning point opening.

Of course these values, which are used as ideal examples of operation can vary within limits.

With the above and other objects in view which will become apparent from the detailed description below, a preferred embodiment of the invention is shown in the drawings in which:

FIG. 1 is illustrative of a longitudinal cross-section through the regenerators and flues of a coke oven battery with heating flues grouped in pairs near the left and righthand sides and in groups of four between said left and right-hand side. The intermediate section A--A of FIG. 1 is representative of a transverse cross-section through the flues and underjet gas ducts, which are supplied from a rich gas main by a rich gas manifold beneath the battery;

FIG. 2 is illustrative of a transverse crosssection through the flues and regenerators of the same coke oven battery of FIG. 1 with a portion of the section designated B-B being shown generally on an enlarged scale in FIG. 4;

FIG. 3 is a schematic horizontal cross-section through the flues as viewed substantially on line 33 of FIG. 4;

FIG. 4 is an enlarged scale vertical cross-section taken substantially on line 44 of FIG. 3, and showing on an enlarged scale generally the section designated BB in FIG. 2;

FIG. 5 is a vertical cross-section taken substantially on line 5-5 of FIG. 3 through the flues;

FIG. 6 is a composite perspective and elevational view schematically showing the connection between the dosing openings with the various openings in the heating flue 4 according to an arrangement as in FIG. 7; and

FIG. 7 shows a further perspective representation of a four flue group with respective connecting ducts and regenerator spaces. The illustrated form of charging of the heating system is representative of a reversing semi-cycle while heating with lean gas.

As in the illustrative drawings herein and also similar to that of the related Patent 3,567,588, the furnace chambers 1 and the heating walls 2 provide a plurality of groups of heating flues 4, which flues are divided from one another by girders 3 or partitions. The heating flues 4 are combined into groups of two as designated at 5 in FIG. 1, at the head end of the chamber 1, and further into groups of four designated at 6 for the remaining groups shown in FIG. 1. Each heating flue has one upper heating point opening 31, one middle heating point opening 32 and two co-planar bottom openings 33 and 34, which are all as shown more clearly in FIGS. 4 and 6 connected through intermediate flues 35 to 38 with the regenerating spaces 39 and 40 of a regenerating compartment 42 (FIG. 5) sub-divided by a longitudinal wall 41 (FIG. 6). The regenerating spaces 39 and 40 in turn are connected through sole flue compartments which are also longitudinally subdivided by a wall 43 with the dosing openings 44 and 45 of the regulating device 46, which openings can be set independently from each other and are located in the crosssectional area of passage.

FIGS. 1, 2, 4, 5 and 7 particularly show that heating flues, in the adjoining longitudinal axis of the furnace and the axis of the block of a heating flue 4, have different heights relative to the upper and middle burning point openings 31 and 32. The manner of measuring the height of these burning points depends on the furnace height and the required operating conditions.

When heating with poor or lean gas in all the burning heating flues 4 a portion of gas and air flows out of both bottom openings 33 and 34. In this case the proportion of the amount of poor gas in relation to the amount of air to be burned is set in such a way that on the bottom of the heating flue there is a combustion with the excess air. The remaining amount of poor gas flows out of the middle burning point opening 32 into the middle combustion plane and burns there proportionately with the remaining air surplus from the lowest combustion plane. The final combustion of the poor gas takes place in the third combustion plane, with the air flowing out of the upper burning point opening 31 with the normal air surplus.

When heating with rich gas, air is introduced through all the burning point openings 31 to 34 of each heating flue. The outflow of rich gas 48 is located on a lesser height above the bottom of the heating flue. The air is distributed to the different burning point openings 31 to 34 in such a way, that on the two lower combustion planes an incomplete combustion always takes place while a final combustion takes place on the third plane in the presence of an air surplus which is normal for a rich gas. Thus when heating with either poor gas or rich gas there are three combustion planes in a heating flue, whereby the combustion in both upper planes takes place in a mixture of air and waste gas, so that particularly with rich gas heating there is an increase of the flame volume. Due to the choice of different heights of the middle and upper burning point openings from one heating flue to the next heating flue, there results in a total five different combustion planes, which brings about a particularly advantageous vertical heat distribution in the heating walls of high furnaces.

The process for operating a regenerative coke furnace is improved during heating with a lean gas by adjusting the dosing openings 44 and 45 so as to provide for a surplus of air being introduced at the lower burning point openings 33 and 34 in the bottom of the flues 4, such that gas flowing out of the middle burning point opening 32 combusts with the gas surplus, and the air flowing out of the upper burning point openings 31 produce the combustion of the remainder. More specifically, a preferred process is such that the lowermost burning point openings 33, 34 are supplied compositely with 40% of the total amount of lean gas supplied, and with 60% of the total amount of air, whereby the remaining amount of 40% air flows out the uppermost burning point 31, and the remaining 60% of the gas total flows out of the middle burning point opening 32.

We claim:

1. A high chambered regenerative coke furnace of the type having separately fed upper, middle and lower located flue-disposed burning points comprising in combination:

a plurality of vertically disposed flues (4) combined in groups (5, 6);

a plurality of composite regenerator compartments (42) corresponding to the number of said heating flue groups (5, 6) and connected via sole flue compartments (44, 45) with regulating device (46) disposed exteriorly of said furnace for dosing or controlling the amounts of the inflowing and outflowing media such as air, lean or poor gas and waste gas to said burning points in said flues (4);

each of said heating flues (4) having means defining therein a pair of lowermost, spaced-apart generally co-planar burning point openings (33, 34), and respective middle (32) and upper (31) burning points;

each adjacently disposed pair of flues (4) in any given groups thereof having said respective middle (32) and upper (31) openings disposed at respectively diflerent heights compared to those corresponding openings of the adjacent flue;

a dividing wall (41) longitudinally dividing each of said composite regenerator compartments (42) into two longitudinally separated, vertical regenerating compartment half portions (39, 40); separate intermediate connecting flues (37, 38) for the respective lower located burning points (33, 34) of a given flue being connected to respectively ditferent regenerating half portions (39, 4.0) of said respectively different composite regenerator compartments and separate intermediate connecting fines (35, 36)

for the respective upper (31) and middle (32) located burning points being connected to the other respectively different half portions (40, 39) of said same respectively different composite regenerator compartments (42) from which said intermediate connecting fines (37, 38) are connected; an independently dosable flue being operatively and connectingly correlated to each of said composite regenerating compartments (42); said independently dosable fines being divided by a longitudinal dividing wall means (43) into a pair of sole flue compartments (44, 45); and a rich gas inlet opening disposed within said heating fine, near the bottom thereof and at a height substantially lesser than said middle and upper burning points; and due to the varying levels of the upper (31) and middle (32) burning point openings in the respective adjacently disposed fines (4), a total of five different combustion planes is provided for any two consecutive or adjacent pair of fines (4), to provide for a more advantageous vertical distribution of heat in vertical portions of the heating walls of high chambered furnaces. 2. A regenerative coke furnace as defined in claim 1 wherein said lines (4) are each divided by spaced apart transverse dividing walls (3); the means defining said middle (32) and upper (31) burning points are such that said burning points are disposed on opposite sides of said flue adjacent said dividing walls (3); and said respective burning points as formed at said opposite sides of said dividing wall being disposed at respectively different heights. 3. A process for operating a high chambered regenerative coke furnace having separately fed upper (31), middle (32) and lowermost (33, 34) flue-disposed burning points,

feedable in part from a lean gas supply, and from air dosing devices (46, 46) disposed exteriorly of said furnace, which process is related to the heating with a combination of the lean or poor gas and air media, the steps comprising in combination:

(a) setting the externally disposed regulating devices (46, 46) so as to establish a combustion in the lines with air being distributed in such a manner as to establish three different combustion planes, one at the lower, co-planar points (33, 34), such that there is a combustion mixture of air and gas introduced thereto in a proportion of approximately 40% of the total amount of lean gas being introduced, together with an amount of approximately of the total amount of air being introduced;

(b) subsequently combusting on a middle plane at the middle burning point (32) by introducing the remaining approximately 60% of said lean gas separately thereto in an amount whereby the gas is in substantially greater proportion to the air, the latter air being derived from that of incomplete combustion occurring at said lower plane;

(c) and finally combusting at the upper burning point (31) by introducing thereat the approximate 40% remainder of the total of air introduced, and which is a greater proportion of air to be mixed and burned with the unburned gases rising from incomplete combustions at both of said lower and middle burning planes; and whereby the combustion in both upper planes takes place with a mixture of air and waste gas.

References Cited UNITED STATES PATENTS 3,373,087 3/1968 Van Ackeren 202-139 X 1,918,926 7/1933 Otto 202-142 X 3,183,175 5/1965 Breitbach et al. 202141 3,476,652 11/ 1969* Grumm 202-142 1,522,421 1/ 1925 Crossen 202'-142 3,431,178 3/1969 Schon 202-143 NORMAN YUDKOFF, Primary Examiner D. EDWARDS, Assistant Examiner US. Cl. X.R. 202-139, 142 

